1. Field of the Invention
This invention relates to suction cleaning apparatus and, more particularly, to a structure facilitating conversion between on-the-floor and off-the-floor suction cleaning therewith.
2. Description of the Prior Art
Upright suction cleaners with provision for accessories for cleaning off-the-floor surfaces such as draperies and walls, etc. are known in the art.
Typically, as exemplified in Snider, U.S. Pat. No. 2,333,494, an access port is provided in the hood of the cleaner head in the vicinity of a rotary beater. A hinged door is biased to sealingly close the port for normal, on-the-floor cleaning operation. To divert the suction path through any of a variety of nozzle attachments, a converter, with a fitting to accept a suction hose, is introduced to the port, deflecting the door about the pivot and intersecting an air passageway between a chamber surrounding the beater and the suction fan. The converter is configured to be in seating and sealing relationship with the air passageway so that the path between the air passageway and agitator chamber is obstructed. The end of the converter in the port has an opening to communicate uninterruptedly between the suction hose and the suction fan.
A serious deficiency of Snider is the requirement that the converter itself be responsible for sealing the passageway from the agitator chamber for off-the-floor operation. Any leakage in the converter diminishes suction in the accessory, reducing its effectiveness.
It can be seen that to maintain the seal in Snider, the bottom of the converter is angled to flushly engage the bottom wall of the air passageway and at the same time an intermediate region of the converter is abutted at a forward edge of the fan chamber. Insertion of the converter is accomplished by deflecting the door with the leading edge of the converter guiding the converter through the port and interiorly of the air passageway. After repeated assemblies, the leading edge may be so deformed that an incomplete seal is formed with the housing at the bottom of the air passageway. In this condition, outside air is drawn through the agitator chamber so that suction is reduced in the accessory.
Another drawback with Snider is that the converter is maintained in position solely by frictional forces. There is no structure disclosed to prevent separation of the sealing end of the converter from the housing, which may well occur in use as the user manipulates the suction hose attached to the converter.
Humphrey, U.S. Pat. No. 2,686,331, discloses a catch mechanism to maintain a converter in seated, sealing relationship with the suction cleaner housing. A pivoting arm has an integral nose engaging in a detent in the converter. The arm is associated with the forward wheels of the suction cleaner and is operable to simultaneously raise the cleaner head hood to disengage the rotary agitator from the floor and lock the converter in position. The latching assembly for the converter is complicated and not capable of operation independently of the wheel mechanism.